Zenius Onion hair oil is a product made from the extract of onions, which is believed to have various benefits for the hair. It is usually made by infusing oil with onion juice or onion extract. Some people use onion hair oil to promote hair growth, reduce hair loss, and improve the overall health of their hair. Zenius Onion oil is also said to help with dandruff and itchy scalp, and it may help to strengthen and nourish the hair shaft. It is usually applied to the scalp and massaged in, and can be left on for a period of time before being washed out. Some people use onion hair oil as a natural alternative to conventional hair care products.